As I'm sure you know, there’s a lot of rebadging and fakery in the CF card market. What I didn’t personally realise was some scammers aren’t using cards with insufficient capacity or just heavily damaged, some of them are using quite good cards that they’re rebadging as premium range ones. I discovered this personally yesterday. I just purchased a 64GB SanDisk Extreme Micro-SDHX card for my Galaxy S5 (because, as you probably know, slow SD cards used in smartphones can cause performance issues across the board, with apps and functions that have nothing at all to do with the SD card, as evidenced by the 2012 paper Revisiting Storage for Smartphones by Hyojun Kim et al from NEC Labs). Not happy to pay the Australia Tax when it can be had on Amazon for US$50, I found one on eBay for a not unreasonable amount (it irks me we can’t get stuff at Amazon prices, but I’m realistic enough to accept a reasonable markup for living so far from the Civilised World). After seven days, the card arrived from Taiwan. I uploaded a backup of my 32GB card to the new one so it would be ready to pop in my phone, but instead of five to ten minutes it took nearly two hours. Hmm, not quite right. So I tested the card with H2testw, which fills the drive and reads it back to check for errors, check capacity and check performance. It really does have the full 64GB available (well, near enough) and there were zero errors detected, but instead of 45MB/s I was seeing ~21MB/s. Not good. I contacted the seller, who said the rated 45MB/s was only ‘peak’, but if I wasn’t happy with the performance I could send it back to him and he’d provide a full refund. Now I have his name and address (or at least one he can be found through). So then I contacted SanDisk, who confirmed that the 45MB/s rated performance is indicative of the sustained read and write performance I should see from this card (no such thing as 'peak' nonsense). They asked me to run Crystal Disk Mark, which I duly fired up - ~23MB/s reads, ~22MB/s writes; again, less than half. (for the sake of completeness, this is connected to a USB 3.0 card reader connected to USB 3.0 ports that I’ve seen sustained 430MB/s throughput over. I even connected up a 32GB SDHC card which gave me 38MB/s read performance using that card reader. Hell, USB 2.0 gear is capable of higher real-world throughput than this card is putting out! So the equipment isn’t the bottleneck, it is purely the card). Now physically this Micro-SDHC card looks legit to my untrained eye. And there are no issues with capacity or error rate – the device seems to work fine for a 20MB/s card. But a 20MB/s card is a third to half the price of a high performance part. That’s quite a lot of easy cash for relabelling cheap cards as premium performance ones. The thing that’s concerning to me is just how many people must be being scammed by this sort of rebadging. This particular seller has nearly 4,600 transactions and a 99.4% positive feedback rating – I can’t be the first person he’s sold a rebadged counterfeit card to. They must all be out there blissfully unaware that the card they have is only giving them ‘ok’ performance, not the high speed performance they actually paid for. During the course of this I came across this eBay guide which has some worrying stuff right at the bottom: “We have been informed that eBay will NOT act unless the trademark owner (SanDisk, Sony, Kingston) contacts them. All buyers report to eBay hoping that the sellers receive permanent suspension for supplying counterfeits are in vain. eBay will ONLY act if directed to do so by your local law enforcement agency or the rightful trademark owner under eBay’s VeRO program.” I don’t know how accurate that is, so I reached out to eBay to find out. Here's the response I received: So that's a better result than I was expecting, although what I'd like to see is that people found to be committing fraud are, you know, referred to the police and charged with an actual crime. As a purchaser, or as someone who helps your less tech-centric friends trawl through eBay to find products at reasonable prices, look out for sellers going out of their way to disclaim certain performance characteristics. For example, the listing of the card I purchased had this text, that sounds pretty innocuous until you realise why they went to the effort to include it: Now on its own, that actually seems fair enough - connecting a high performance card into a performance limiting card reader will indeed result in poor performance figures (although bear in mind that USB 2.0 has a theoretical maximum bandwidth of 60MB/s and should pretty easily hit 40MB/s in a real-world scenario - it definitely should not top out at ~22MB/s). However, most flash card sellers don't go to this effort - being pre-emptive suggests that this is a problem and a question that they experience routinely. On its own, such 'advice' or disclaimer doesn't necessarily mean the listing is dodgy, but it should be a flag to make you sceptical. Another fairly obvious flag was the claim that the item was not in retail packaging, but instead in 'bulk' packaging, consisting of a 'small plastic case'. It is much harder for counterfeiters to reproduce the retail packaging with holographic stickers, so they will avoid this if possible. Again, not comprehensive proof of fraud in and of itself (I've purchased a lot of stuff off eBay that was legitimately genuine but shipped without the retail packaging), but definitely a flag that should trip your caution-meter. SanDisk have offered to replace my card, which IMO is pretty exceptionally great of them. Obviously I’m protected by PayPal and eBay’s Buyer Protection program, but having SanDisk willing to replace this fake card with a genuine one is pretty fantastic, so kudos to them. They haven’t seemed particularly keen to explore the possibility that the card might be fake at this stage though - they've been quite reticent to directly answer any such question. But they may not be willing to do so until such time as they have inspected the card themselves - it would be pretty disastrous for them if they accused a legitimate distributor of selling counterfeit products! If the above is correct about only a rights holder (SanDisk) being able to file a complaint with eBay, they may also be trying to collect evidence before taking it further. This is the point my story is at - I expect to hear back from SanDisk to confirm shipping arrangements Monday. eBay have been informed of the problem and have promised to investigate. But that's still not going to stop the problem - the only way to do that is to ensure the buying public are far better informed. Or, you know, end geographically disparate regional pricing behaviour - if everyone has access to products at Amazon (and similar) prices, they don't have to go hunting through eBay to feel like they're not being routinely raped by greedy Australian stores.